1. Field of the Invention
The present invention relates to a wall-mounting image processing apparatus having both an image reading function and an image printing function.
2. Description of the Related Art
A prior art image processing apparatus has such a structure as shown in FIG. 9, for example. The illustrated image processing apparatus includes a machine housing 2e in which an image read/write head Ae is accommodated. The machine housing 2e also accommodates a document D, a recording paper K, and an ink ribbon 9 capable of thermally transferring images, all of which are transferred along respective transfer paths within the housing 2e. 
The image read/write head Ae, which serves as both a read head and a print head, includes an elongated head case 1e. The head case 1e accommodates a plurality of light sources 30e and a plurality of lenses 51e. Each of the light sources 30e and the lenses 51e is arranged in a respective row extending in a primary scanning direction, i.e. longitudinally of the case 1e. The head case 1e is provided with a transparent plate 19e which provides an image read line Se extending longitudinally of the case 1e. The head case 1e is provided, at the bottom thereof, with an elongated substrate 4e which has an obverse surface provided with a row of light receiving elements 3e. The substrate 4e also has a reverse surface provided with a row of heating elements 8e. Each of the rows of light receiving elements 3e and heating elements 8e extends in the primary scanning direction.
In the image processing having the above-described structure, the document D is transferred by a platen roller P3 to pass over and across the image read line Se so that an image of the document D is read line by line. On the other hand, a recording paper K is transferred by a platen roller P4 in close contact with the heating elements 8. During such transfer of the recording paper K, selected ones of the heating elements 8e generate heat, so that images are printed on the recording paper K line by line.
The image processing apparatus having the above-described structure can be made smaller than an image processing apparatus in which a read head and a print head are separately provided. Further, the use of an ink ribbon 9 makes it possible to use an ordinary paper as a recording paper K. This is advantageous, because if a thermosensitive paper is used as the recording paper K, there exist various problems that the printed image deteriorates in a relatively short time, for example.
However, the prior art image processing apparatus still has the following problems.
In the prior art apparatus, a pair of winding cores 90a, 90b for the ink ribbon 9 are arranged in the machine housing 2e in such a manner that they are spaced from each other in a plane which is roughly parallel to the reverse surface of the substrate 4. Further, both of the cores 90a, 90b are located on one side of the substrate 4e, as viewed thicknesswise of the substrate 4e. With this arrangement, it is possible to smoothly transfer the ink ribbon 9 along the reverse surface of the substrate 4e. 
With this structure, however, if the image read/write head Ae has a relatively large thickness or height H (the distance between the image read line Se and the heating elements 8e), the image processing apparatus becomes correspondingly bulky. This is because the thickness or height of the image read/write head Ae is entirely additional to the thickness or height of the image processing apparatus as a whole.
On the other hand, there is a higher need for overall thickness reduction of the image processing apparatus, particularly, for using the image processing apparatus as a wall-mounting type facsimile machine for example. However, such a thickness reduction is not possible in the above-described prior art.